The cases of 19 patients sent to the emergency room by a dose of “mad” honey highlight the not-so-sweet side of the food, according to Turkish researchers.

The honey, produced from the nectar of certain rhododendron species, has long been linked to food poisoning, with most of the documented cases occurring in Turkey. In the country’s Black Sea region, mad honey is used as an alternative medicine for gastrointestinal problems and as a sexual stimulant.

However, the honey can contain substances called grayanotoxins, some of which may cause low blood pressure, slowed heart rate, vomiting, dizziness and other symptoms.

In the 19 cases reported in the November issue of the Emergency Medicine Journal, most patients had dips in blood pressure and heart rate, and all suffered nausea, vomiting, dizziness and weakness. Four had a complete atrioventricular block, in which electrical signals fail to pass normally from the heart’s upper chambers to the lower ones.

The patients, all seen in one ER in 2002, responded well to treatment with the drug atropine, said lead study author Dr. Hakan Ozhan, of Abant Izzet Baysal University of Duzce.

Although most instances of poisoning by mad honey have occurred in Turkey, rhododendron species in other countries also have the potential to yield toxic honey, Ozhan told AMN Health.

And, he and his colleagues note, with the growing consumption of imported and unprocessed “natural” honey worldwide, the possibility of honey intoxication should be kept in mind whenever a healthy person has an unexplained drop in blood pressure and heart rate.

Processed honey, according to Ozhan, would not be expected to contain grayanotoxins. And, he noted, it’s also easy for a beekeeper to know whether a nest contains mad honey, because it tastes different from the non-mad variety.

In Turkey, Ozhan pointed out, people knowingly buy mad honey to use as medicine or to boost their sexual prowess.

Many of the patients in this report had ulcers, he and his colleagues found. And, Ozhan noted, a number were grooms who had eaten the honey in preparation for their wedding nights.

SOURCE: Emergency Medicine Journal, November 2004.